1. Technical Field
The present invention relates to the manipulation and storage of information. More particularly, the present invention relates to securing information against unauthorized use while permitting time-limited and/or function-limited use and/or examination of the information.
2. Description of the Prior Art
Most expression and communication is reducible to one form or another of information. As information technologies become more and more sophisticated, information is increasingly being treated as a commercial commodity. For example, movies may be purchased or rented on video-tape; music is stored digitally on compact disks; computer programs are available on floppy disks; and data bases, including images and text, are readily available on CD-ROM, as well as from on-line services.
As with any commodity, it is easier for a potential purchaser to make a purchase decision if he or she is able to evaluate the information before making the decision. Because most information exists as ephemeral material, such as is stored electronically on a magnetic medium, or as is broadcast over the airwaves as an electronic signal, it is difficult for a vendor to secure the information against unauthorized use in its original form during a trial or evaluation period.
It would be beneficial to reconcile these conflicting concerns with regard to transactions involving such materials. That is, it would be helpful to a vendor of such materials if a potential purchaser were able to evaluate a secure, original version of the materials during a trial period. Because such materials are expensive to purchase but easy to copy illegally, it is common practice for a potential purchaser to obtain and evaluate an unlicensed copy of the materials. This allows the potential purchaser to avoid purchasing such materials at significant cost and then never use the materials because they do not meet the purchaser's needs. It also allows the potential purchaser to continue using an unlicensed copy of the materials after evaluation is completed, resulting in significant lost revenues to the vendor of the materials.
The various techniques that are known for securing evaluation versions of ephemeral materials are, overall, unacceptable to both a potential purchaser and the vendor. For example, such techniques require that the original author of the material devote significant time and energy to modifying such material to create a trial or evaluation version of the material. The vendor is then obligated to inventory and support nonrevenue producing versions of the vendor's products.
If, after a trial period, a user desires to purchase the material, it is not possible to employ a remote transaction to deliver such materials. Rather, the customer must place an order with the vendor and the product must be shipped to the customer from inventory. This series of transactions creates delays that may frustrate the customer, while adding significant overhead to the vendor's operations. Thus, it is not possible for a vendor to take full advantage of all possible material distribution channels. For example, when delivering pay-for-view and other entertainment media to a customer over a broadcast medium, it is not possible to deliver high-bandwidth evaluation versions of the material, and then provide an enabled, fully functional version of the material by means of a low-bandwidth transaction, e.g. over point-to-point channels, such as by telephone, at a conclusion of the trial period.
Accordingly, trial versions of such materials, such as software products and other forms of electronic data, are specially modified versions of the material that have intentionally limited functionality and that cannot be restored to their original state. Customers are encouraged to use the trial version of the material and then, if the customer wants to purchase a fully functional, unrestricted version of the material, the customer must order the standard material version. The trial version of the material is then discarded. Typically, such trial versions provide very limited functionality, such that the potential customer cannot get a realistic view of the product.
The following schemes comprise the state of the art with regard to providing trial and evaluation versions of ephemeral materials, such as electronic data:
A data access system provided by Enigma Logic of Concord, Calif. allows the evaluation of the full or standard version of a software program--the system does not work with data, such as images or sounds. A remote transaction is necessary to allow access to, or enabling of, the software product. Accordingly, the evaluated program cannot be converted locally to the standard, unmodified version of the program. The data access system allocates algorithm space to software authors, but includes software hooks in evaluation versions of the program. Such evaluation versions must be recompiled into special versions that incorporate the unique enabling programs. This requires special software or a unique operating system for implementation.
More problematic is the requirement that a separate password gate and hardware key is necessary to allow use of the system. Such scheme degrades both system operation and program performance by requiring the user to interrupt use of the program and respond to frequent validation calls to the password gate.
Lotus Software of Cambridge, Mass. provides an evaluation system that allows a user to evaluate a full or standard version of a software product that must be stored on a hard disk. The system requires remote confirmation before a user is allowed access to, or enabling of, the software product. The system also requires that a software author modify the original software to implement the evaluation scheme, such that the evaluation version must be recompiled before it can be enabled. The system additionally includes a routine that provides hardware copy protection.
"Trial Versions" of software are generally available. Such versions are often offered for free or for a nominal charge and provide some restricted utility of the software product, which allows a user a limited evaluation of the product. As with other evaluation schemes, this system requires that the software author modify the original product to produce the evaluation copy. If a user decides to purchase the product, the user cannot create a fully functional, full featured copy of the original product remotely, but must purchase another disk which contains an operational original version of the product.
Encrypted broadcasts are commonly used, for instance for Pay-Per-View showings of movies and other entertainment programming. Such system does not allow unrestricted viewing of a full original version of the program. Rather, the version of the program provided to a viewer is intended for one-time use. Thus, such system is not useful for most applications involving electronic data which require many-time use of programs, databases, art, music, etc.
Adobe of Mountain View, Calif. provides a CD-ROM-based evaluation system for printer fonts. This system requires a remote transaction to access a fully enabled version of the stored fonts. However, the system only allows viewing of the fonts on the user's screen. The computer system printer metrics are not provided in the trial or evaluation versions of the font. Thus, printing is possible only when the enabled version of the font is available. Accordingly, such a scheme, because it only allows viewing of the font on a screen, is of no practical value in evaluating the actual printed font on a page of paper.
Comstock of New York, N.Y. provides a library of stock photos on CD-ROM. The system allows viewing of a scanned digital version of a full original (i.e. a low resolution version), but does not allow for remote unlocking of the original. Rather, the system requires a separate transaction to obtain fully usable copies of the library photos.
Examples of other schemes for protecting ephemeral materials include:
DAT (Music Tape) copy protection;
Floppy Diskette copy protection;
Serial Port hardware keys;
Restricted number of copies of original;
"Try and Buy", i.e. specially developed trial versions of original materials that cannot be converted to originals, collected on a CD-ROM, e.g. MacWorld Resource CD.
The foregoing systems are of limited use and appeal because they require the author to modify the original material to produce the evaluation version of the material. As such systems provide a less than completely functional evaluation copy, a non-owner cannot evaluate the entire original material, for example in making a purchase decision. Should the decision be made to purchase the original, an entirely different copy of the material must be obtained, i.e. an evaluation copy of the material cannot, upon validation, be used as a fully functional original of the material.
There is not any known secure system available at this time that allows a user to view a data-based product, or use the product in its fully functional form before deciding to purchase the product, and that allows the user to restore the evaluation version of the product to its fully functional original version form immediately after the user decides to purchase the material.